A house edge is expressed per unit wagered, not per session. A 1.41% edge on a craps pass line means that across a very large number of bets, the house expects to keep about $1.41 of every $100 staked. It says nothing at all about tonight.
Two things multiply it into a real cost. Bets resolved per hour decides how many times the edge is applied, which is why a fast one-roll proposition drains a bankroll far quicker than a line bet at the same percentage. And total money at risk matters more than the headline figure, which is why adding free odds at 0% lowers your blended cost without changing any individual number.
Edges across a casino floor range enormously. Free odds in craps are exactly zero. Baccarat's banker bet is 1.06%. American roulette is 5.26% on every wager. The worst sic bo total is over 47%. Games that look similar are frequently priced very differently, and the number is rarely displayed.
Where the numbers come from
Related terms in odds & money
- RTP — Return to player: the mirror of house edge, quoted as what comes back rather than what is kept.
- Expected value — The average result of a bet if it could be repeated indefinitely.
- Variance — How widely results scatter around their expected value.
- Standard deviation — A measure of how far results typically stray from the average.
- Bankroll — The money set aside for gambling, kept separate from money needed for anything else.
- Unit — One standard bet, used as the yardstick for measuring results and bankroll.
Where an entry quotes a number, that figure comes from the computed sections of this site rather than from another glossary, so the definition and the derivation cannot drift apart. Each entry links to the page where the number is worked out.